SAO PAULO/FRANKFURT, Dec 10 (Reuters) - Eneva SA, the Brazilian power producer controlled by Germany’s E.ON SE and tycoon Eike Batista, filed for creditor protection late on Tuesday after failing to refinance part of its 2.33 billion reais ($900 million) in debt.

In a statement, Eneva said court protection from creditors will allow the ailing power producer to preserve cash and continue its operations. Following the decision, Eneva appointed Alexandre Americano as chief executive officer, replacing Fabio Bicudo, who will become chairman.

Eneva, formerly MPX Energia SA, is the fourth company controlled by Batista’s commodities, energy and logistics conglomerate forced to seek protection from creditors over the past year. E.ON gained control of Eneva following the collapse of the conglomerate, known as Grupo EBX. Batista founded MPX in 2001.

Shares of Eneva slumped 20 percent in São Paulo trading on Wednesday, while E.ON gained 1 percent in Frankfurt. Filing for bankruptcy protection in Brazil allows the company to suspend debt payments to creditors and present a revamped business plan within 60 days.

E.ON changed MPX’s name to Eneva last year and hired Bicudo to turn around the company by cutting costs and accelerating the completion of some projects. Under Bicudo, Eneva boosted power production to the equivalent of 2.4 gigawatts, earning around 2 billion reais in revenue over the past 12 months.

Net income and core earnings at Dusseldorf, Germany-based E.ON, which owns 43 percent of Eneva, would not be affected by Eneva’s bankruptcy protection petition.

The German utility reduced the value of its stake in Eneva by 340 million euros last year. Currently it is worth around 100 million euros, a E.ON spokesman said.

“Eneva suffers from a lack of liquidity caused by a combination of operational issues, a stressed market environment and high levels of debt and interest,” E.ON said in a statement on Wednesday.

Eneva operates seven thermal electricity plants that were not included in the petition. The request for bankruptcy protection encompasses the holding company and its Eneva Participações SA unit.